Method for using motor fuels



Patented er. a. 19cc THOMAS minaret; an, or Barron, OHIO, ASSIGNOR, BY mnsnu nssrermnurs, 'ro' GENERAL morons coaronarrou, or nnraorr, mromean, a. coaroanrron or DELAWARE METHOD FOR 'USTNG M01363 FUELS fNo Drawing. Original applicationfiled April 15, 1922, Serial No. 553,270. Eatent No. 1,573,846, dated February 23, 1926. Divided and this application filed January 22, 1926. Serial No. 83,133.

This invention relates to fuels, such, for example, as kerosene and-gasoline, employed in the operation of internal-combustion engines and to the art of burning the fuels in an engine. .Thepresent tendency is to produce lower grades of gasoline in order to obtain a suflicient output for the increasing demand for motor fuels and to reduce the compressions of the engines so that these lower grades of fuel may be used without knocking. As the lowering of engine compression reduces the efficiency of the engine, a still greater output of fuel is required to meet the increase in fuel required to operate larger and less efiicient engines. The prin- .cipal objects of the present invention are to overcome these difficulties and to provide ameans for using either low or higlr grades of motor fuel more efficiently and so reduce the quantity of fuel used.

The resent application is a division of my co-pen ing application Serial No. 553,270,

ture may be burned in a cylinder without producin'g a fuel knock varies with the different fuels and, to'some extent, with the temperature, position of spark plugs and other conditions within the engine. This pressure I term the critical compression pressure of the fuel.

The average critical compression pressure of kerosene is about 50 pounds, of the poorer grades of gasoline about ounds and of the better grades of gasoline 9. out 125 pounds. The latter grade of gasoline is produced in limited quantities and is not available universally to the consumer. The commoner grades of fuel, such as kerosene and gasoline, having critical compression pressures below 75 pounds are used generally, and internalconibustion engines for house lighting sys- I terns, trucks, tractors, and automobiles are designed to operate on these kinds of fuel.

I have found that the critical compression pressure of a fuel of the type mentioned above is increased by incorporating therewith any one of a large number of compounds containin metallic elements i. e., compounded metallic elements.

By way of example, I may use a fuel consisting by volume of of one percent of tetra ethyl lead and 99% per cent of gasoline having a normal critical compression pressure of about 75 pounds. The tetra ethyl lead dissolves in the gasoline forming a fuel having a critical compression pressure of about 160 pounds. The presence'of the lead compound changes the gasoline from a low compression fuel to a higher compression fuel i. e. increases its critical compression pressure. This gasoline may be used in an engine having a compression pressure of about 160 minds with a smaller fuel consumption for obtaining a given amount of work than is required to operate an engine having a compression pressure of 75 pounds on the untreated gasoline. Experiments with automobiles have shown that if the engine compression is increased to 160 pounds, a treated fuel being used to run the engine and the gear ratio between the engine and the rear axle is reduced, the mileage obtained from a gallon of gasoline is substantially twice that obtained when running the engine at 7 5 pounds com ression on the untreated or low compression uel.

For some commercialpurposes ,it will probably be sufficient to usebut one part of tetra ethyl lead in 2000 parts of asoline. This mixture may be used in a 'trudkmotor climbing hills at low speed with open throttle. Relatively small proportional quantities of the lead compound are required to increase the critical compression pressure of aviation gasoline from 125 pounds to 160 pounds or more.

The fuel'nrixture or combination may also bevaried by using other fuels as the fuel base ,to avoid the-knock generally produced when w or major'constituent of the high compression fuel and using other compounded metallic elements" to increase critical compression pres-v sure. The fuels used include gasoline and other hydrocarbon fuels containing hydrocarbons which may be obtained from an asphalt, naphthene, parafiine base crude or mixtures thereof.

Other lead compounds which have been used successfully are the phenyl compounds and other alkyl compounds besides tetra ethyl lead. propyl and method compounds. Methods of manufacturing lead compounds are described on page 134 et. seq., Vol. 111 of l/Vatts Dictionary of Chemistry as revised by Morley andMuir and published by Longmans, Green and Co., London, England.

Other metallic compounds may be used to suppress a knock in a motor. These include compounds of selenium, tellurium, tin, ar-

I do not limit my invention to organic compounds nor to the oil soluble compounds.

The value of metallic compounds in changing the critical compression pressure depends upon the metal used, the composition of the compounds, its stability and volatility. Up to the point of complete vaporization the auti-knock value depends in part on the percentage of the compound vaporized under engine conditions. Where the nature of the compound changes before ignition of the fuel, combustion of the fuel takes place. in the presence of the new compound and the anti-knock value depends on the nature of the new compound instead of the compound added to the fuel. I

If'a radical is attached to the metal in the compound in such a manner that the result-' ing compound is oil solubleand volatile, a high anti-knock value for that metal is obtained. As thecompound departs from these conditions either in the kind-of radical emplayed or the number of radicals of acertain kind in the compound, the anti-knock value based on these conditions, becomes negligible are lead oleate and lead acetate. If, in the These include the ethyl, iso-- claims which follow.

nature. will generally be reduced. Examples of compounds in which the anti-knock value, as f j Volatile and less soluble in the fuel than the tetra ethyl lead. The tri-ethyl lead hydroxide is almost as powerful a knock suppresser as the tetra ethyl lead.

The value of a compounded metallic element as a knock suppresser appears also to be a period function of the atomic number and, in general, with similar elements increases with increasing atomic weight. To illustratethis function,I takethe ethylcompounds of the metals in the right hand column of the 4th, 5th, and 6th groups, wherever stable ethyl compounds are obtainable. As the ethyl compound of antimony is unstable in the air at room temperature, I employ the phenyl compound of antimony. These compounds increase in knock suppressing value in group 4 inthe order tin, lead; in group 5 in the order arsenic, antimony; and in group 6 in the order selenium, tellufium. Taking group 4 as an example, 1% by volume. of the ethyl compounds of the metals in gasoline or kerosene give the following increases critical compression pressure: tin, 15 pounds; lead at the rate of 340 pounds when employed =in relatively .small quantities. \Vhile I have mentioned more particularly the use of phenyl and alkyl compounds of certain metals for increasing the critical compression pressure of-kerosene and gasoline, my invention is not limited wholly to the use of these compounds', nor to compounds of these metals, and the compounded metallic elements may be employed with the heavier hydrocarbon or other fuels.

Further, while the specific examples here- .in given constitute preferred forms of embodiment of the invention, it is to be understood that other forms might be adopted, without departing from the scope of the Iclaim: 1. A method of utilizing a low compression motor fuel which comprises forming a compounded metallic. element.

. 2. A method as defined in claim 1, in whieh' l the gaseous low compression fuel is burned in the presence of a vaporized alkyl compound of a metal.

3. A method as defined in claim 1, in which the gaseous low compression fuel is burned in the presence of a gaseous ethyl compound of a metal. 1,

- In testimony whereof I hereto afiix my sig THOMAS MIDGLEY, JR.

formula for tetra-ethyl lead, an OH radical is substituted for an ethyl radical, the resulting,

compound (tri-ethyl lead hydroxide) is less 

